Further to Geoff and David's comments, Varied Tit is listed by Brazil (1991) as one of the three most popular cagebirds in Japan. It apparently adapts well to captivity, can be taught to do tricks, and is/was used in the fortune-telling trade.
Brazil also paints a picture of Varied Tits of the various Japanese subspecies being highly sedentary on their islands, staying within well demarcated territories. It may be that juveniles disperse but the Po Toi bird and the bird in the photos I've seen from the container terminal island in Zhejiang are all adults.
